J. Miguel RamirezPhysics Teacher

Hanna High SchoolBrownsville ISD

Dr. Katy KaoAssistant Professor

Department of Chemical EngineeringTexas A&M University

• Develop mutated strains of fluorescent yeast (S. cerevisiae) with enhanced production of carotenoids. – Traditional chemical synthesis of carotenoids is difficult because of

its unique structure and cost.• This will be accomplished by applying a selective pressure to

the cells which will cause generation of mutants with enhanced properties.

• Hydrogen peroxide (H2O2) was chosen as the selective pressure. – Carotenoids have a natural antioxidant property – Organisms that are able to grow in an oxidized environment will

have enhanced carotenoid production

GFP

RFP

YFP

0.00 mM H2O2

0.050.10.20.40.81.02.0

TECAN® Microplate Reader

Growth Kinetics Curves

VISUALIZING EVOLUTION IN REAL-TIME Identify when adaptive events occur Facilitate the isolation of adaptive mutants

VERT is based in the generation of fluorescent strains by integrating different fluorescent proteins into microbial cells

Red Discosoma Coral

Aequoreavictoria

Property of Dr. Kao Group

Lab Objective # 2: Identify parameters involved in enhanced production of carotenoids

GFP

YFP

RFP

FL2-H

FL1

-H

FL1-H510/21 nM

FL2-H585/42 nM

FL1-H650 nM

FL3-HF

2-H RFP

FLUORESCENT ACTIVATED CELL SORTER

Property of Dr. Kao Group

Fluorescent Activated Cell Sorting (FACS) machine

Counts heterogeneous and homogeneous mixtures of cells One at a time Extremely fast and efficient

Distinguishes cells by their light scattering and fluorescence emitted. Compares to particular

wavelengths of visible light Sorts and plots them using the

electromagnetic spectrum.

• 2F and 2G Demonstrate use of equipment, techniques, and procedures; make accurate measurements.

• 3A and 3E Critical thinking and make connections between physics and future careers.

• 7A,7B, 7C, 7D, 7E, and 7F Investigate and analyze characteristics, behaviors, and interactions of waves, sound, and light. Describe and predict image formation as a consequence of reflection from a plane mirror and refraction through a thin concave and convex lens.

• Short lecture describing the most important and most difficult to understand areas of waves.

• Video clips and pictures that help students visualize some of the interactions and effects of waves.

• Overview on electromagnetic waves and the spectrum.

Questions: 1.What is the difference between a transverse and a longitudinal wave?2.What are some of the differences between sound and light?

• Class demo on wave interference using the super slinky.– Constructive and destructive interference using a water

bottle.– Demonstrate a transverse and a longitudinal wave.

• CPO Sound & Wave lab demo– Correlation between frequency and wavelength in the lab

and the EM spectrum.• Explore reflection, refraction, diffraction, absorption,

and polarization using flashlights, lasers, polarized glasses, and prisms.

Questions: 1.Why does sound travel at different speeds in different types of matter?2.What happens in refraction? Why?

• Explanation of lab project:– Present poster and explain.– FACS machine and how it is used.

• Engage students to scientific engineering and how it relates to real life jobs and equipment used.

• Students will be given a 50 cell sample of three different fluorescent yeast cell strains grown each with a specific protein enhancement. – The wavelength of light emitted for each cell will be

given and students are to sort and plot cells.– A real life situation will be given as the problem at

hand.

GFP

YFP

RFP

FL2-H

FL1

-H

FL1-H510/21 nM

FL2-H585/42 nM

FL1-H650 nM

FL3-HF

2-H RFP

FLUORESCENT ACTIVATED CELL SORTER

Property of Dr. Kao Group

Cell Sample

Wavelength (nm) Frequency (x1014 Hz)

1 680 ?

2 720 ?

3 550 ?

4 480 ?

5 589 ?

6 655 ?

7 623 ?

Students will solve for the frequency before being able to plot on the graph. To solve they must convert from nm to m, then use the speed of a wave formula with the speed of light as 3.0 x108 m/s.

Formula: v = f • λ

• Students will finish counting, sorting, and plotting the sample of cells they were given.– The graph and table with the information of the cells

will be displayed on a poster board.– Poster board will be displayed in the class room. – Look for the correct amount of individuals for each

population, at the correct wavelength according to the light emission given, and the correct frequency.

• Students will identify what color has the biggest and smallest wavelengths and see the relationship between frequency and wavelength.

Questions: 1.What is the correct order of the colors in visible light (largest to smallest)?2.What color has the biggest waves? Smallest waves?

• Students will make a plot similar to this.• They can see how wavelength and frequency

are inversely proportional.

• Lecture on lasers and optics including concave and convex lenses.

• Video showing the importance of lasers and optics in real world applications and professions.

• Class demos of reflection, refraction, and diffraction using lasers.

• Allow students to play with the concave and convex mirrors so they can see the difference.

Questions: 1.How are lasers being used in professions today?2.What is the difference between a concave and a convex lens?

• Explanation of engineering design process using examples of good vs. bad engineering and engaging students to use imagination and creativity to build something.– Example: Ask students to develop a plan for our classroom. The

students will be given constraints and certain dimensions and rules that they have to follow. Let students brainstorm the problems of the classroom and ideas on how to fix them.

• Show pictures and examples of engineering around the world.• Videos:

– A world of glass– Engineering professions

Questions: 1.What engineering profession is the best fit for you?2.What ideas do you have for the future?

Courtesy of Project Lead The Way

• Students will plan a path using the engineering design process for a laser to reach a desired location (inside a cup of water).– They will get a real life story/situation where this problem can apply.

• Restrictions will include:– Have to use three mirrors.– Laser beam will start at a fixed location of about 20 cm above lab table.– Lasers have to be at least 30 cm apart.– They will have to use trigonometry to find the correct angles and distances.– Laser must enter a glass of water where they will have to measure the index

of refraction (Snell’s Law).– Students may use any time of materials or tools to hold mirrors in place.

• Students will be encouraged to plan accordingly, brainstorm, and take into account the restrictions while planning.

http://phet.colorado.edu/en/simulations/category/physics

Helpful Links and Simulations

http://games.erdener.org/laser/

• Finish construction of laser path and test it.– Measurements must be made before actually trying

the laser.– Students have to give a brief explanation of their

design.• Students get only two tries to achieve their goal.

– This will prevent trial and error but at least allow them to make adjustments if something was wrong.

• Extra points will be given for creativity, amount of supplies used, time taken, and accuracy based on a specific rubric

Questions: 1.In reflection, how is the angle of incidence different than the angle of reflection?2.What are some of the differences between sound and light?

ACKNOWLEDGEMENTS

TAMU E³ Program National Science Foundation Nuclear Power Institute Dr. Katy Kao Luis H. Reyes (Ph.D. student) Other lab members:

• Priscila Almario

• Mian Huang

• Yuqi Guo

• Sisi Thomas (partner)